Governor



Nov. 2 1926.

iE. M. JOHNSON GOVERNOR Filed July 1 4, 1920 2 Sheets-Sheet 1 V mum/Taf? si Ma/Emsa D A l A TT'RNEYS Patented Nov. 2, 192.6,

UNITED STATES wenn ERNEST JOHNSON, OF JERSEY CITY, NEX/V JERSEY, ASSGNOR TOV EDWARDYV. HART- FORD, 0F DEALNEW JERSEY; HENRIETTA POLLlTZER HARTFORD ADMINISTRA- TRIX OF SAID EDWARD V. HARTFORD, DECEASED.

Govnmion.

'Application filed my i4, 192e. serial No. 396,218.

In all governor design the speed and closeness of regulation at that speed are assumed quantities, and from these quantities, and others, the detailsv are worked out. the governorshereto'fore known to ine, `the closeness of regulation varies in soine fashionwith the speed. That is, the usual inechanisin which is satisfactory for one predeterinined speed is entirely unsuited for lanother speed, by reason of the 'fact that centrifugal forces vary with the square of the speed, at a constant radius of gyration. of this, it has been difficult to regulate the speed of variable speed machinery to a satisfactory degree. I s i- 'One of the :objects otniy invention vis to provide a governor which is capable of close `regulation o'fj the speed of variable `speed yiinacliinery, more i .particularly i one in which the closeness of regulation of speed, through- 'out a long range in speed, is, tor-all practical purposes, independent' of 'the speed. f

Anotherobject of my inventioniis the provision, ina close regulating governor, ot one or more` ot the following features? (l) adjustability of speed while running, (2); low energy consumption in the sustaining ot the governor parts in position, ininiinuin wear otparts, accessibility forinspection, (5) 'a natural period far" aboveany speed likely to be atta-ined.` y

Another object of my invention is to provide instruinentalities which may be utilized to transinit to an external medium the disturbances setup by the goxfernor wherever the speed falls below or exceedsthat tor which it is set, so that an energy supply inay be controlled. In the embodiment set forth ,in the drawings an electric switch is'shown,

to control the energy supply of a inotor.

-, "Other objects of iny invention will appear as the description ot theillustrated einbodinient of my invention shown in the 4drawings proceeds, and l desire-itrto be understood that the specitic description ot iny invention is intended as illustrative rather thanliiniting the invention.

ln the drawings:

Fig. l is an elevation, with, the cover reinoved, ota governor made in accordance with my invention, showing it in connection `with an electric motor and a switch.

ln all Y On account Anected to the control-screw. Y (Theleltt end 37; of the armature -tube 445i p delinitelylocatednon the post` 32 `and aligned K Fig. 2i is a section on the line 2 2 of F ig. l; and f i Fig. 3 shows the characteristic curves for a typical governor. p rlhe governor is shown as being driven from the` left end 37 of the shatt oit afseries electric motor `whose armature and iield are diagraininatically represented at .18V and 19. The motor 4is supplied from 1nains20` and 2l through a relay 22 whose coil 23 vis.;con nected by a lead 25 to a movable ,Contact 28. This contact cooperates with a fixed contact 2,7 connected by lead 26 to the other side of the line. The break may Vbe shuntedby-a resistance and capacityv 24. l

Anunder-traine 29 having an annular end yscrew 36 which is connected to -a hand-wheel V15.A `The outer surface.3 5: .,offthis-bearingis machined to take the thrust ci a spring-contends beyond the end-trame ot the motor and has a diainetral slot orgroove V38 cut therein. This slot or groove is adaptedto receive an outwardly extending tongue from van eleinent connectedv to drive thegovernorshaft.

On the post f32 is -inounted a bearing-heus! ing 39 whichy supports a-` ball-bearing i-O. Thebearing 40 is held in position by the end-part Lwhich is grooved at 42, in order to Iretain lubricant in tha bearingV rEhe housing -39 is also grooved.` as at 43 to-retain lubricant in place. The lubricantmay tbe supplied from the grease-cupv 4,34 throughthe rThe bearing-housing y inay be by ineansof dowel-pins, as 46,a-nd shoulders,

l as 47. Y

rlhe lug or post 33 onfthezfrarne29 sup- .ports anotherbearing-housing i8 which is lheld iirnoly in' place byv suitable bolts ,49,

dowel-pins- 50,'and shoulders 5l. rEhe housing 48, at the lett,- supports a ball-bearing 52. This bearingis held in place by an end-plate 53, provided; with!y a lubricant retaining groove 541-. y The housing 48j also supports a shaft eX- yshown and shouldered at 89.

thrust-bearing 55, the housing in this ease extending to the right far enough to inclose the bearing, where it is provided with a 1ubricant retaining groove 56. The lubricant may be supplied by means of grease cup 44 through the tube 45.

The bearings 40 and 52 support a shaft 57 on which are mounted the rotating governor parts. The right hand end of the shaft 57 is shouldered at 58 to receive the bearing 40 and is threaded at 59 to receive the threaded end 60 of a member 61 which has integral thereof a tongue 62 for engagement in the slot 38 in the motor shaft 37. The member 60 is pinned to shaft 57 at 60', and clamps the inner member of bearing 40 against shoulder 58.

The other end of the shaft 57 is shouldered at 64 'to receive the bearing 52. The shaft is shouldered at r65 and threaded at 66 to receive a nut 67 which is adapted to clamp the inner member of the bearing 52 in place.

The shaft 57 has a long key 68, fixed to it. All ofthe rotating elements of the governor, to beI described, are driven through this key and are adapted to slide on the key, to a limited. extent. At the left, the hub 69 of Yspider-shaped member 70 is mounted. The

hub v69 is shouldered at 71 where it lits the thrust-bearing 55. The spider-shaped memvber 70 has four arms, two of which, 72 and veach bifurcated at 76 and 77 and a hardened 'steel shaft 78 having a knife edge 79, is supported by these bifurcations. The arms 74 and 75 are similarly provided with bifurcations which extend to the dotted lines 81 and 82. Steel shafts 83, knife-edged at 84,

'are supported within the bifurcations 80.

A long sleeve is supported on the shaft 57 and adapted to slide on key 68. This sleeve has an annular shoulder 86 to receive the thrust of a small helical spring 87. The

other end of this sleeve is threaded as The intermediate portion of this sleeve is profvided with two keys 90 and 91, Afixed thereto on which another sleeve 92 is adapted to slide. The end of the latter sleeve abuts against the other end of the spring 87. A collar 93 is threaded on the sleeve 85 and one part 94 of a ball-bearing 95 is mounted on the shouldered end 89 of this sleeve.

The arms 72 and 73 of the spider 70 carry, by means of the knife-edged shafts 79, two bell-crank members 96 having short arms 97. The sleeve 85 is cut away at 85 to provide shoulders 86 against which rollers 98 on arms 97 abut. The other arms 99 of the bell-cranks 96 are provided with weights or balls 100. These weights, when the governor is idle, are held against the outside of a flange 101 on sleeve 92, by a spring to be described.

The arms 74 and 75 of the member 70 carry, on the knifeedged shafts 83, bellcrank members 102. Each of the members 102 supports on its arms 103 a ball or weight 104. Each of the other arms 105 of the bellcrank members 102 has a pivot-pin 106 on which one end of a connecting member 107 is mounted. The sleeve 92 has two outstanding oppositely disposed bifurcated ears 108, which carry pivot pins 109. The other end of each of the connecting members 107 is connected to one of 'the pins 109. When at rest the spring 87 will hold the arms 103 next the bottom wall 81 of the bifurcations 80. At this time there is a slight clearance, two small to appear on the drawing, between sleeve 92 and collar 93.

An annular housing 110 having the crosssection shown in Fig. 2, is provided for the thrust-bearing 95, and has a grease-cu 111, lubricant retaining grooves 112 an two vknife-edged members one of which is clearly shown at 113 in Fig. 1. These knife-edged members are fastened to the outside wall of the housing on opposite sides of the central y opening through which the shaft 57 passes. The bearing 35 for the control-screw 36 is provided with a small inwardly extending The major portion of this screw is threaded as shown at 117. The free end of the screw is provided with a nut 118. This 'nut is guide-d by means of a member 119 con- "nected to a pointer 16, which slides in a slot V16 in the cover 14 and by a second member (not shown) adapted to slide in a groove 118 in the under-frame 29. I

One end of a comparatively large spring cooperate with an eye 121. The eye 121 is suitably connected to a knife-'edged member 122 which rests in a notch 123 in a balancing lever 124. This lever is provided with a notch 125 intermediate its ends, which notch is adapted to receive the knife edged niembers 113 and 114. The other end of the lever 124 is notched as at 126 to cooperate with a vertical knife-edged member 127, supported on a post 127 carried by the under frame 29. The lever 124 is shown in section in Fig. 2, .and is provided with an aperture 128 wsomewhatl 'larger than the 'shaft 57 which passes therethrough.

The bearing-housing 39 supports on the' top thereof a slab 129 of insulating material on which are mounted the switch contacts 27 and 28 and mechanism for operating same from an arm 130, attached to a post 130 which is in turn supported by the lever 124.

"119l fits over the nut 118, and the other end K of this spring is provided with a hook 120 to longer arm 132 of this bell-crank member is provided at its free en'd with a T-head having downwardly bent ends on which are mounted screws 135, adapted to be locked in place by lock-nuts 136. The bell-crank member is pivoted at 137 on a fixed member 138 which is also provided with a horizontal grooved pin 139.

Intermediate the ends of the arm 132 there is supported on the slab 129 a C-shaped member 149, carrying a knife-pivot equipment, indicated in broken lines in Fig. 1, near the terminus 149 of the upper or crown curve of the C. One of such pivots is carried by the underside of said crown curve of the C, and the other by the upper side of the bottom curve of the C; the pivots being vertically aligned. A member 156 is mounted as a lever on these bearings. rl"his member, which is also shown in 1, being there shown only in top plan; but being a U- shaped member in side elevation, so that the legs of the U, one vertically above the other, have their free ends presented in the vicinity of said knife-pivots for attachment thereto to give the member 156 its lever mounting. The lower leg of the member 156 is located in theplane of the screws 135, carried by the down bent ends of the T-head of arm 132 of the bell-crank lever. A spring 159 is fastened to the central portion of the U-shaped member 156 and hooked in the groove of post 139. This spring will bias the member 156 to one side or to the other side of its knife-pivot mounting. The member 156 is held to a limited range of movement by means of adjustable stops 160 and 161. The

` central portion of the U-shaped member 156 `similar to the U-sliaped member 156.

'able lock nut is employed.

has fastened on each side thereof the Z-pieces 162 an'd163, thereby providing bifurcations. The outer end of each of these Z-shaped members 162 and 163 is provided with adjustable stops as shown. j

The movable switch contact 28 is pivoted on knife-edged members indicated in broken lines in Fig. 1, and supported in a member 174 similar in shape to 149 and in a fashion A part of the Contact 28 is between the ends of the stops on Z-pieces 162 and 163. The

switch 28 is biased to one side or to the other .side of its knife-pivots by means of a spring 171 connected to the central part of the switch member and to a post 172 carried on `the insulating slab 129. A suitable binding post 173 is connected to the C-shaped member 174 which supports the switch element. The other binding post 175 for supporting the fixed contact `is provided with means to adjust the position of the fil-red contact. In this case a screw 176 provided with a suit- The extent of movement of the switch element 28 in the opposite direction is limited by means of an adjustable stop 178 similar to the afore-described means except that it is not electrically connected to a lead.

The cover 14 which is over the governor and switch, is fastened in place by suitable means not shown. with a removable plug 180 to afford access to grease cup 111, without necessitating the removal of the cover.

The adjustment of the speed at which the governor will control the motor is made by if;

means of the hand-wheel 15. By this handwheel the member 118 can be moved'to the left or right, thereby adjusting the tension under which the spring 119 is to be placed. VThe pull developedV in the spring 119 is transmitted by means of the lever 124 to the knife-edges 113, carried on the housing 110. The housing 110 floats on the bearing 95 carried on the sleeve 85 on shaft 57. ihe

force transmitted from the lever 124tothis housing, on account of the symmetry of the device, becomes an axial thrust through the housing 110, bearing 95, sleeve 85, shoulders 86', rollers 98, bell-crank member 96, knifeedged shafts 78, spider-shaped member 70,

and thrust bearing 55, which abuts the fixed bearing-housing' 48, carried rigidly by the under frame 29.` The balls 100 are held upon the flange 101 of sleeve 92, by this thrust when the governor is at rest.

' According to the design of this governor, the balls 104 are freev to move about their pivotsand assume a position which will depend Aupon the speed iat which the Vdevice is operating and the characteristics of spring u 87, but not upon the pull developed in spring 119. The balls 104 as they move back and forth will operate against the spring 87 in a fashionsimilar to the ordinary fly-ball governor. l/Vhen'at rest the spring 87 merely lreacts against the flange 86 and the sleeve develop-sufficient force not only to overcome l the thrust transmitted to the sleeve 85 from the. spring'119 but also to overcome the rcaction of spring 87 against the flange 86,

and, moreoventhe amount of force which is to be developed by this latter spring will depend upon the position in which the free balls 104 are. It is thus apparent that While the balls 104 and the parts they operate are free to assume a position depending upon y, the speed at which the governor is driven,

This cover is provided' llt) . poses the pull exerted by the spring 119.

yet the balls 100 which may be termed the restrained balls, are not able to move away from the aXis and assume a position determined solely by the centrifugal force developed and the tension of the spring 119.

It is well known that the centrifugal force developed by a mass varies directly with the radius of gyration and with the square of the speed. If a plot is made showing the centrifugal force obtained at various speeds at a constant radius of gyration a parabola will be obtained. Since the centrifugal force developed is a function of both the radius of gyration and the square of the speed, the curve to be obtained by plotting the centrifugal force against the speed, where the governor balls are permitted to fly outwardly so that the radius of gyration increases with the speeds is not a true parabola but it indicates that the centrifugal force increases at a different rate.

The balls 100, whose radii of gyration are substantially invariable, for reasons to be pointed out, develop centrifugal forces which vary with the square of the speed, i. e., substantially parabolically.

In the governor shown in the drawings the free balls 104 with their connecting parts constitute a simple governor whose characteristic curve is of the type last described. The design and proportion of the parts is made so that the thrust developed in the spi ng Sloy the free balls 104 opposes the een@ ifugal force developed by the balls 100.

The centrifugal force developed by the balls 100 acts through the rollers 98 upon the flange S6 of the sleeve 85 and thence in an obvious manner to the lever 124 and (lps before pointed out, the amount of tension in the spring 119 can be regulated by the hand wheel 15. Hence it appears that by increasing tension in the spring 119 the balls 100 may be urged inw rdly more strongly. It is also apparent that the operation of the free balls 104 and the parts they move, is directly opposed to the operation of the restrained balls 100 and the parts they move.

The resultant or cumulative centrifugal force to be delevoped by the combined devices will be the difference between that developed by the balls 100 and that developed lby the balls 104. This is represented in Fig.

3 by a plot. The curve A is a parabola representing the centrifugal force developed by the Xed or restrained balls 100, the curve B represents the characteristic performance of the free balls 104`and parts operated thereby. lWhen the curve B is subtracted from the vcurve A, the characteristic curve C' for the composite governor is obtained.

The more closely the curve C approximates straight line, the more nearly constant will bc the absolute regulation of motor-speed by the governor. The matter of securing a straight line for the curve C is one of design and may be obtained by carefully computing the centrifugal forces developed by all the parts of the governor in their various positions and at corresponding speeds and the forces necessary to deferm the springs. In practice the design can be made such, for example, that if the governor regulates to within revolutions per minute at 1,000 revolutions per minute, it will regulate to within about 52 to 55 revolutions per minute at 5,000 revolutions per minute. its a practical matter, the designer should not attempt to make the line C absolutely Straight because then, there might possibly occur points of inflection in this line which would indicate that the governor was unstable at some particular or critical speeds.

ln order to control the energy supply to the motor fzom such a sensitive governor, a very delicate switch is provided in the reiav circuit. The switch is operated by the arm 130 connected with the lever 124. Thel arm 130 operates a bell-crank the long arm 162 of which carries as above described the adjustable stops 135. rl`his bell-crank arm will move ba ck and forth in accordance with the movements imparted to the lever 124 by the balls 100 which when the motor is running are a slight distance from the llange 101. They must move, however, a finite distac-e before the stops 135 will touch the lower portion of the U-shaped member 156 and force said member past dead-center, so that the coiled spring 159 will snap the member 156 quickly against the limiting stop. The member 156 does not itself make electrical Contact to open or close the circuit, but it is provided with adjustable stops on its Z-pieces 162 and 163 which engage with the tongue on the movable switch element 28 to pull it to one side or the other side of dead center so that the spring 171 can snap it either away from the fixed contact 27 of the switch or against the fixed stop 178. The delicate mechanism above decribed will not stick at any point nor can it flutter. It either makes a goed contact or a clear break.

ln the operation of the governor, the switch already described will'be open at all times when the speed is in excess of that determined by the setting of the tension of the spring 119. As soon as the speed drops helow that, the over-powering action of the balls 104 is removed, and the balls 100 can then fly out a slight distance and thereby operate the mechanism to close the switch. The closing operation is similar to the opening operation above described.

1t is thus apparent that the difference bevtween the forces developed by the composite governor at aspeed of X and at a speed of X-m will be all that is available to operate the switch. The distance through -Which this useful force moves will alsobe very small. It is in fact determined by the build-up of the spring 119 necessary tosustain the increment in centrifugal force developed by the governor. The switch above.

ply is in the present embodiment an electric switch, I Would have it understood that other instrumentalities may be employed, as ,for example, valve ports may be opened or closed. e

I claim:

l. In con'ibination, tivo sets of centrifugal elements each mounted to have a variable radius of gyration, and means associated with each set of elements to oppose increase in the radius of gyration thereof, each means controlling yielding elements and being sus@ ceptible of adjustment during the'operation of the governor. L

2. In combination, two sets of centrifugal elements each mounted to have a variable radius of gyration, and yielding means associated with each set of elements to oppose increase in the radius of gyration thereof, each means controlling yielding elements and be-` ing susceptible of adjustment during the operation of the governor.

3. In combination, tivo sets of centrifugal elements each mounted to have a variable radius of gyration, and spring means associA ated with each set of elements to oppose increase in the radius of gyration thereof, each means controlling yielding` elements and being susceptibleof adjustment during the op eration of the governor.

4. In combination, two sets of centrifugal elements each mounted on a common support to have a variable radius of gyration, and

means associated with each set of elements to oppose increase in the radius of gyration thereof, each means controlling yielding elements and being susceptible of adjustment during the operation of the governor.

5. In combination, tivo sets of centrifugal elements each mounted to have a variable radius of gyration, means associated With each setof elements to oppose increase in the radius of gyration thereof, and means to vary one of the aforesaid means Whilethe governor is operating.'

6, In combination, two sets of centrifugal elements each mounted to have a variable radius of gyration, yielding means associated with each set of elements to oppose increase in the radius of gyration thereof, and means to vary one of the aforesaid means While the governor is operating.

7. In combination, two sets of centrifugai elements each mounted to have a variable radius of gyr'ation, spring `means associated with each set ofelements to oppose increase i in the radius of gyration thereof, andinea'ns to vary one of the `aforesaid means Whilethe governor is operating.

8. ,In combination, tiro sets of centrifugal elements each mounted on a common support to have a variable radius of gyration, spring means associated with each set of elements to oppose increase in the radiusV of vgyration thereof, and means to vary one ofthe afore said means While the governor is operating.'`

9. In combination, a first set Ofcentrifugal elements mounted to have a variable ra,- dius of gyration, a second set of'` centrifugal elementssimilarly*mounted, means opposing means for opposing an increase in the radius of gyrationin the second set, and meansA to transmit the opposition set up by the first means to the-,second set of centrifugal elements to thereby oppose an increase in they radius of gyration thereof, the'parts being so arranged as to be susceptible of adjustment While the governor is operating.

galelements mountedtoliave'a variable radius Vof gyration, a second set ofv centrifugal elements similarly mounted, spring meansV opposing an increasefin the ra'diusfof gyration of the first set,-spring' means independent of the first means for opposing an in-f an increase `in the radius of gyration theres" of, the parts being so arranged as tobe susy ceptibleof adjustment whilefthe governor is operating.

l1. In combination, a first set'of centrifugal` elements`mounted to have afvariable radius of gy'ration, af second set of centrifugal 5 elements similarly mounted, means opposing an increase in the radius of gyration'V of the first set, means opposii'igan increase in the radius in the second "set, means to transmit tlieopposition. set up by thel first means toV the-second set of' centrifugal elements toV thereby oppose an ,increase in the radius ofV gyration thereof, and means to vary the opposition set up by the second means.

l2. In combination, a irstset' of centrifu` gal elements mounted to have avariable radius of gyration, a second set of'centrifugal elements jsimil'arlyV mounted, spring means opposing an increase in the radius of gyra- -tion of the first set, spring means "opposing l an increase in ,the radius of gyration inthe second set, means .to transmit the opposition 4set up bythe iirst means to the second set of centrifugal elements to thereby oppose ann' increase in the radius 'of gyration there/off I an increase in the radius of gyration of theifirst set, means independent vof the firstV V.90 l0. In combinationa first set of centrifu-V;

and means to vary the opposition set up by the second spring means while the governor is in operation. Y

13. In a variable speed governor, two sets of centrifugal elements each mounted to have a variable radius of gyration, means associated with each set of elements to oppose an increase in the radius of gyration thereof, means to vary the opposition of one of Athe aforesaid means, and means to algebraicallysummate the forces developed centrifugally whereby a speed-centrifugal force characteristic may be secured which differs from that of each set of elements while the governor is in operation.

14. In a variable speed governor, two sets of centrifugal elements each mounted to have a variable radius of gyration, yielding means associated with each set of elements to opposean increase in the radius of gyration thereof, means to vary the opposition of one of the aforesaid yielding'means, and means to algebraically summate the forces developed centrifugally whereby a speed-centrifugal force characteristic may be secured which differs from that of each set of elements while the governor is in operation.

15. In a variable speed governor, two sets of centrifugal elements each mounted to have a variable radius of gyration, a spring associated with each set of elements to oppose an increase in the radius of gyration thereof, means to varythe opposition of one of the aforesaid springs, and means to algebraically summate the forces developed centrifugally whereby a speed-centrifugal force Vcharacteristic may be secured which differs from th-atfof each set of elements while the governor is in operation.

16.V In a variable speed governor, two sets of centrifugal elements each mounted on a common support to have a variable radius of gyration, a 'spring associated -with each set of elements to oppose an increase in the radius of gyration thereof, means to vary the opposition of one of the aforesaid springs, and means to transmit the sum of the centrifugal forces whereby7 a speed-centrifugal force characteristic may be secured which differs from that of each set of elements `while the governor is in operation.

17. In a governor; a shaft; a sleeve slidably mounted thereon; a spring opposing theV movement of the sleeve in one direction; means to adjust the tension in thespring;

` a first set of centrifugal elements opposing the movement in the opposite direction; and means to restrict the movement of said first set of centrifugal elements at all speeds below the speed correspondingy to the tension in the spring, said last mentionedv means comprising a secondv set of centrifugal elements and opposing means therefor tovpermit theV radius of gyration thereof to increase with the speed, the parts being so arranged as to be susceptible of adjustment while the governor is operating.

18. In a governor; a shaft; a sleeve slidably mounted thereon; a spring opposing the movement of the sleeve in one direction; means to adjust the tension in the spring; a first set of centrifugal elements opposing the movement in the opposite direction; and means to restrict the movement of said first set of centrifugal elements at all speeds below the speed corresponding to the tension in the spring, said last mentioned means comprising a second sleeve on the first sleeve, a second spring intermediate the second sleeve and the first sleeve, and a second set of centrifugal elements associated with the second sleeve to compress the second spring with increase in speed.

19. In a governor; a shaft, a sleeve slidably mounted thereon; a spring opposing the movement of the sleeve in one direction; means to adjust the tension in the spring; a first set of centrifugal elements opposing the 'movement in the opposite direction: means to restrict the movement of said first Y set of centrifugal elements at all speeds below the speed corresponding to the tension in the spring, said last mentioned means comprising a second set of centrifugal elements, and opposing means therefor to permit the radius of gyration thereof to increase with the speed; and a common support for both sets of centrifugal elements, said support being carried by the shaft.

20. In a governor; a shaft; a sleeve slidably mounted thereon; a springopposing the movement of the sleeve in one direction; means to adjust the tension in the spring, a first set of centrifugal elements opposing the movement in the opposite direction; means to restrict the movement of'said first set of centrifugal elements at all speeds below the speed corresponding te the tension in the spring, said last mentioned means comprising a second sleeve on the first sleeve, a second spring intermediate sleeve and the first sleeve, and a second set of centrifugal elements associated with the second sleeve to compress the second spring with increase in speed; and a common support for both sets of centrifugal elements, said support being carried by the shaft.

21. In combination, a shaft, a fixed support, a lever pivotally mounted transversely of said-shaft, a spring associated with the lever to urge the lever in one direction, means carried on the shaft cooperating with the lever to balance the same and transmit the force to the fixed support, and speed responsive mechanism carried on the shaft and associated with said means to vary the tension in the spring only when the speed exceeds a predetermined amount.

the second of said shaft,an adjustable spring associ-V ated with the lever to variably urge the lever in onedirection, means Vcarried on the shaft cooperating..withipthe `lever to balance the same and transmit the force to the lined support, and speed responsive mechanism carried on. the shaft and associated with said means to vary the tension in the spring only when the speed exceeds an amount determined by said adjustment.

23. in combination, a shaft, a fixed support, a lever pivotally mounted.transversely of said shaft, a helical spring whose axis is parallel with the shaft, associated with the lever to urge the lever in one direction, means carried on the shaft cooperating' with the lever to balance the same and transmit the force to the fixed support, and speed responsive mechanism carried on the shaft anni associated with said means to vary the te onin the spring only when the speed exceeds a predetermined amount.

2li. ln combination, a shaft, a fined support, a lever pivotally mounted transversely of said shaft, ,a spring` sociated with the lever to urge it in one direction, means carric'd on the shaft cooperating with the lever to balance the same and transmit the force to the 'tn-ref. support, and speed responsive.

mechanism having a speed-centrifugal force characteristic carried on the shaft and associated with said means to vary the tension inthe spring only when the speed exceeds a predetermined amount.

25.wln a compound governor; a shaft; a sleeve lreyed thereto; tivo sets of centrifugal elements, oneset reacting directly against the sleeve, the other set reacting against the sleeve through a yielding instrumentality, said reactions being in opposite directions; means to support the centrifugal elements and drive them from the shaft; and a yielding instrumentality exerting a. thrust on the sleeve, one of the sets of centrifugal elements and one of the yielding instrumentalities constituting a simple governor, the other of centrifugal elements and the other yielding instrumentality constituting another simple governor, said two governors having different speed-centrifugal force characteristics so interrelated that the forces in the sleeve may be neutralized at one speed.

26. ln a. compound governor; a shaft; a sleeve keyed thereto; two sets of centrifugal elements, one set reacting directly against the sleeve, the other set reacting against the sleeve through a helical spring which surrounds the sleeve, said reactions being in opposite directions; means to support the centrifugal elements and drive them from' the shaft; and a second spring exerting a thrust on the sleeve, one of the sets of centrifugal elements and one of the springs constituting a lsimple governor, the othery set of centrifugal elements and the other spring constituting another simple governor, said two governors having different speed-v centrifugal force characteristics so interrelated that the forces in the sleeve may be neutralized at one speed.

27. lin a compound governor; a shaft; a`

sleeve keyed thereto; two sets of centrifugal elements, one seti'eacting directly against the sleeve, the other set reacting against the" sleeve throughV a yielding instrumentality. said reactions being in opposite directions; means to support the centrifugalu elements and drive them from ti e shaft; and an adjustable yielding instrumehtality exerting a thrust on the sleeve, one of the Asets 'of centrifugal elements `and one of the yield-. ing instrumentalities. coi'istituting a simple governorY having lined performance, the otherset of centrifugal elements and the adjustable yielding` instrumentality constituting another simple governor having adl ble perforn'iance so interrelated that forces in the sleeve may be neutralized '.t a selected speed.

28. ln a compound governor; ashaft; a sleeve hej-,fed thereto; .two sets of centrifugal elements, onefset reacting directly against the sleeve,'the vother set reacting against the sleeve through a helical spring Vwhich surrounds the sleeve, said reactions being in opposite directions; means tol support the centrifugal elen'ients and drive 'them from th-e shaft; and an adjustable spring eI-:ert-

' ing a thrust on the sleeve, one of the sets the helicalK of centrifugal elements and spring constituting a simple governorhavingl .a liv. centrifiio'al elements and the adjustable spring constituting another simple governor having adjustable performance so interrelated that the forces in the sleeve may be neutralized at a selected speed.

29. ln a governor, the combination with a driving shaft, of a speed responsive mechanism associated therewith, said mechanism having a speed-centrifugal force characteristic and including sets of centrifugal elements each supported by the shaft to have a variable radius of gyration, and means to algebraically summate the centrifugal forces developed in the respective sets, whereby the governor is of substantially constant absolute sensitivity at various speeds.

30. In a governor, the combination with a driving shaft, of a speed responsive mech.- anism associated therewith, said mechanism having a speed-centrifugal force character-A istic and including sets of centrifugal` elements each supported by the shaft to have a variable radius of gyration, and means to algebraically summate the centrifugal forces developed in the respective sets, and an inful strumentality responsive to substantially the same increment of speed of the speed responsive mechanism at various speeds.

31. In a governor, the combination with a horizontal driving shaft, of a speed responsive mechanism associated therewith, said mechanism having a speed-centrifugal force characteristic and including sets of centrifugal elements each supported by the shaft to have a variable radius of gyration independent of gravity, and means to algebraically summate the centrifugal forces developed in the respective sets, whereby the governor is of substantially constant absolute sensitivity at various speeds.

32. In a governor, the combination with a driving shaft of a speed responsive mechanism associated therewith, said mechanism having a speed-centrifugal force characteristic and including centrifugal elements supported by the shaft to have a variable radius of gyration, means to algebraically summate the centrifugal forces developed in the respective sets, whereby the governor is of substantially constant absolute sensitivity at various speeds, and stops for the centrifugal elements when at rest.

33. In a governor, a shaft, a plurality of sets of centrifugal elements, a common support for said centrifugal elements carried on said shaft, a member, and means associated with each set of, centrifugal elements to impose upon the member in opposite directions the forces developed centrifugally in said centrifugal elements whereby they may be algebraically added, the parts being so arranged as to be susceptible of adjustment While the governor is in op-V eration.

34. In a governor, a shaft, a plurality of sets of centrifugal elements, a common support for said centrifugal elements carried on said shaft, a sleeve carried by the shaft, and means associated with each set of centrifugal elements to impose upon the sleeve in opposite directions the forces developed centrifugally in said centrifugal elements whereby they may be algebraically added, the parts being so arranged as to be susceptible of adjustment while the governor is in operation.

35. In combination, a shaft, a plurality of sets of centrifugal elements, a common support for said centrifugal elements carried on said shaft, a member, means associated with each set of centrifugal elements to impose upon the member in opposite directions the forces developed centrifugally in said centrifugal elements whereby they may be algebraically added, and an instrumentality responsive to the movements of the member caused by unneutralized forces therein,l the parts -being so arranged as to be susceptible of adjustment while the governor is in 0peration.

36. In combination, a shaft, a plurality of sets of centrifugal elements, a common support for said centrifugal elements carried on said shaft, a sleeve loosely keyed to said shaft, means associated with each set of centrifugal elements to impose upon the member in opposite directions the forces developed centrifugally in said centrifugal elements whereby they may be algebraically added and the sleeve may slide on the shaft, and a yswitch responsive to the movements of said sleeve.

ERNEST M. JOHNSON 

